Figure 2.

(A) Belt design and IMU fixation. (B) IMU placement and coordinate conventions. A segment coordinate system was defined as anterior (+x), proximal (+y), and medial–lateral (with right defined as +z), and adduction–abduction/right downward–upward tilt/right–left lateral bending, internal–external rotation/left–right axial rotation, and flexion–extension/anterior-posterior tilt were defined about the x, y, and z axes with the right hand rule [42]. (C) The reference IMU (blue location) was ‘correctly’ placed anterosuperior to the right lateral malleolus (shank), on the superior aspect of the right iliac crest in line with the greater trochanter (pelvis), or on the superior aspect of the sacrum in line with the spine (sacrum). A single ‘misplaced’ IMU was then positioned 0.03 m proximal and either 0.04 m to the left or right of the reference IMU (in the red and purple locations). (D) Experimental setup.